The article discusses some methods for testing the ability of cancer cells to metastasize. A review of the most important methods for the study of this phenomenon both in vivo and in vitro. Wideomikroskopii discussed the use of methods for the direct observation of metastasis formation in vivo, and most of the methods in vitro: 2 - and 3-dimensional tumor cell population confrontation and correct, the method passing through the basement membrane proteins coated filters in the Boyden chambers, organotypic cultures, locomotor activity test method kokulturach tumor cells to normal cells, and three-dimensional collagen gels. The paper presents the basic assumptions of these methods, and discusses their limitations.